All text that is not markup or comment constitutes the character data of the document (known as CDATA).
CDATA is just like PCDATA, except the parser will not expect child XML content to be embedded in it.
If you want to embedded reserved characters xml character in your document, you need to enclose them in a cdata section.
An example of a CDATA section, in which
andare recognized as character data, not xml markup:
<![CDATA[<greeting>Hello, world!</greeting>]]>